An improved method for quantifying sedimentary charcoal via a volume proxy

In charcoal analysis, number and area of charcoal particles are the most commonly measured parameters. However, neither measurement is precise as charcoal fragments can be broken into smaller pieces during preservation and laboratory processing, and then both number and apparent area will increase. Volume is a more reliable parameter than area to represent charcoal amount but is difficult to measure. However, a simple approximation provides a stable and reliable proxy estimate of charcoal volume. By applying the formula C Sigma A(i)(3/2) (where C is a constant, A(i) is area of a charcoal particle, and Sigma means sum), measures of area are shown to be convertible to volume. The constant may be estimated empirically if enough experimental data are available. Even if C is not precisely quantifiable, the application of Sigma A(i)(3/2) as a stable parameter provides a good first approximation to measurements of convert area to estimates of volume. Empirical experiments demonstrate that volume estimates reduce the error induced by fragmentation or loss of tiny pieces during processing or measuring.